<template>
  <view>
    <!-- 使用自定义搜索组件 -->
    <my-search @myclick="gotoSearch"></my-search>
    <view class="scroll-view-container">
      <!-- 左侧的活动区域 -->
      <scroll-view scroll-y="ture" :style="{height:wh + 'px'}" class="left-scroll-view">
       <block v-for="(item,i) in cateList" :key="i">
         <view :class="['left-scroll-view-item', i === active ? 'active' : '']" @click="activeChanged(i)">{{item.cat_name}}</view>
       </block> 
      </scroll-view>
      <!-- 右侧的活动区域 -->
      <scroll-view scroll-y="ture" :style="{height:wh + 'px'}" :scroll-top="scrollTop">
       <view class="cate-lv2" v-for="(item2,i2) in cateLevel2" :key="i2">
         <!-- 二级分类标题 -->
      <view class="cate-lv2-title">/{{item2.cat_name}}/</view> 
        <!-- 三级分类列表 -->
        <view class="cate-lv3-list">
          <view class="cate-lv3-item" v-for="(item3,i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
            <!-- 三级分类图片 -->
            <image :src="item3.cat_icon" ></image>
            <!-- 三级分类文本 -->
            <text>{{item3.cat_name}}</text>
          </view>
        </view>
       </view>
      </scroll-view>
    </view>
  </view>
</template>

<script>
  export default {
    data() {
      return {
        // 当前设备可用的高度
        wh:0,
        cateList:[],
        active: 0 ,
        // 二级分类列表
        cateLevel2:[],
        scrollTop: 0
      };
    },
    onLoad() {
      // uni.getSystemInfoSync()系统api
     const sysInfo = uni.getSystemInfoSync()
    this.wh = sysInfo.windowHeight - 50
    
    this.getCateList()
    },
    methods:{
      // 获取分类列表数据
     async getCateList(){
     const {data:res} = await uni.$http.get('/api/public/v1/categories')
     if(res.meta.status !== 200) return uni.$showMsg()
     this.cateList = res.message
     
     // 为二级分类赋值
    this.cateLevel2 = res.message[0].children
    
      },
      activeChanged(i){
        this.active = i
        
        // 重新为二级分类赋值
        this.cateLevel2 = this.cateList[i].children
        this.scrollTop = this.scrollTop === 0 ? 1 : 0
      },
      // 调整到商品列表页面
      gotoGoodsList(item){
        uni.navigateTo({
          url:'/subpkg/goods_list/goods_list?cid=' + item.cat_id
        })
      },
      gotoSearch(){
      uni.navigateTo({
        url:'/subpkg/search/search'
      })
      }
    }
  }
</script>

<style lang="scss">
.scroll-view-container{
  display: flex;
  
  .left-scroll-view{
    width: 120px;
    
    .left-scroll-view-item{
      background-color: #F7F7F7;
      line-height: 60px;
      text-align: center;
      font-size: 12px;
      
      &.active{
        position: relative;
        background-color: #FFFFFF;
        
        &::before{
          position: absolute;
          top: 50%;
          left: 0;
          transform: translateY(-50%);
          content: ' ';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #C00000;
        }
      }
    }
  }
}
.cate-lv2-title{
  font-size: 12px;
  font-weight: bold;
  text-align: center;
  padding: 15px 0;
}
.cate-lv3-list{
  display: flex;
  flex-wrap: wrap;
  .cate-lv3-item{
    width: 33.33%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    image{
      width: 60px;
      height: 60px;
    }
    text{
      font-size: 12px;
      margin: 10px;
    }
  }
}
</style>
